Enzymatic Extraction of Sapodilla (Manilkara achras L.) Juice: Process Optimization and Characterization

Abstract

Conventional treatment of sapodilla pulp yields very viscous, turbid, and low juice recovery. Sapodilla processing for juice requires liquefying enzyme that leads to rectifying flow of juice. This study was conducted to optimize the enzymatic pectolytic conditions of sapodilla fruit processing to extract maximum juice using a central composite design (CCD). The effect of processing variables on recovery of juice, total soluble solids (TSS), viscosity, clarity, and L-value along with physicochemical analysis was investigated. The optimized processing conditions were pectinase concentration (0.120%) at 42.02°C for 167.83 min resulting in juice recovery (62.08 ± 0.38%), viscosity (4.81 ± 0.02cP), TSS (21.48 ± 0.19 °Brix), clarity (0.72 ± 0.05%T), and L-value (28.79 ± 0.96). Optimized sapodilla juice showed higher filterability (24.16 ± 1.04 min-1), conductivity (69.46 ± 0.30 S/m), total phenolic content (35.86 ± 0.60 mg/100 mL), ascorbic acid (6.38 ± 0.58 mg/100 mL), moisture content (84.85 ± 0.21% WB), and titratable acidity (0.143 ± 0.0% citric acid) as compared to control sample (60.5 ± 1.80 min-1, 30.43 ± 0.35 S/m, 30.68 ± 0.85 mg/100 mL, 4.64 ± 0.0 mg/100 mL, 83.69 ± 0.18%, and 0.130 ± 0.0%). Optimized sapodilla juice was lower in sedimentation index (0.73 ± 0.11%), turbidity (13.73 ± 1.10 NTU), ash (0.57 ± 0.031%), and β-carotene (0.173 ± 0.008 μg/100 mL) as compared to control sample (1.07 ± 0.02%, 79 ± 0.75 NTU, 0.65 ± 0.031%, and 0.306 ± 0.007 μg/100 mL). The flow behavior index (n) was closer to 1 in both juice samples, which indicated Newtonian-like flow behavior. Conclusively, sapodilla juice extraction at optimal condition (0.120% of pectinase concentration) and 42.02°C/167.83 min would be potentiated to the beverage industry. The use of pectinase might reduce membrane fouling and facilitates processing operation efficiently.